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Any update on this?  I could really use a working IE version.  I test across different browsers so having a sync that works across the big three (Firefox, Chrome. IE/Edge) is key for me.  I have never had the IE sync work.

Is there any hope of ever getting IE to work?  It's going on a year now.

Any word on an IE fix?  6 weeks since I passed on the information and there's been nothing.

I'm also paying for this.  Part of the justification for paying was that it worked for IE.  But it doesn't.

FIrefox and Chrome merge normally.   I've also been able to update Firefox and Chrome from the set on the server (use the server data as the master and overwrite local with it).  I use the server set the first time I set up any new copies of Firefox or Chrome.  I've tried to to the same "update from server" to initialize the IE set from what's on the server.  I have not tried a regular merge from IE because what I have in IE locally is pretty old.  

IE then fails with the error everyone has shown above.  At that point, the bookmarks in IE are all messed up.  I can recognized some but the folder structure is not there, I see duplicates, etc. -- what's in IE after it fails looks very little like the master set other than having some of the bookmarks that are in that set.

Account is:

For IE, I'm selecting Overwrite Local Data (Download).  That's because it's been so long since my IE bookmarks updated I don't want to risk a merge -- I know what's on the server is the set I want.   Once I get a clean new set into IE Favorites I plan on merging -- that's what I do with Firefox and Chrome.

When IE fails it leaves the bookmarks (Favorites) pretty much a mess.  So I always end up restoring from the last backup (which has always worked so far).